An aqueous solution of `6.3 g` oxalic acid dihydrate is made up to `250 mL`. The volume of `0.1 N NaOH` required to completely neutralise `10 mL` of this solution is

Options

A. 40 mL
B. 20 mL
C. 10 mL
D. 4 mL

Answer

A

Explanation

6.3 gm `(COOH)_(2).2H_(2)O` in 250 ml dihydrate oxalic acid
`(6.3)/(126)` mole `(COOH)_(2).2H_(2)O` in 0.25 l `(COOH)_(2)2H_(2) = 126 "gm/moles"`
Hence molarity of acid is 0.2 M `6.3 rarr 0.05` moles
n -factor of `(COOH)_(2)/2H_(2)O` is 2 `:.` Normality of `(COOH)_(2).2H_(2)O = M xx "n-factor" = 0.2 xx 2 = 0.4 N`
meq of acid consumed = meq of Base consumed
`0.4 xx 10 ml = 0.1 xx V_(ml) rArr V_(ml) = 40 ml`